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make a waist caul use a large dowel don't just press with press screw that will create pressure points

Thanks for your comments John. I watched your video on bending figured maple sides a few times before attempting my bend. I did use a waist caul and I also have the controller and other components from you.

My problem occurred when I tried to tighten the wing nut at the end of an eye bolt holding down the lower bout clamp piece and it kept slipping off repeatedly. The more I put it back in place & tightened it the more it kept slipping out of the slot in the block. I spent too much time trying to fasten it down and didn't realize the controller was set to full with the temp climbing higher & higher. I woke up when I smelt wood burning. Does that qualify me as being "woke"?

Anyway, I made new hold down pieces without a slot for the eye bolt. However, I intend to replace the eye bolt system with springs. That way I can avoid fiddling with eye bolts & wing nuts. As I said previously this was entirely my fault due to inexperience even though I attempted to do everything right.

John, please clarify which of the following is correct, or does it matter?

In your updated bending video the sandwich layers from the bottom up are:
slat / wet paper / wood / wet paper / blanket / slat on top

In your reply yesterday to this thread the layers are:
slat / wet paper / wood / wet paper / slat / blanket on top.

Thanks for your help.

we are here to help

DG - Here's my setup in case it might be helpful. My center caul is much larger than necessary but you get the idea. The springs on the hold downs are a big help. If springs are not readily available bungee cords might work?

This was my first bend and I used aluminum flashing which worked, but I have spring steel on the way from John. IIRC my sandwich went like this, from the top down to the form: flashing/blanket/flashing/paper/wood/paper/flashing.

I used butcher paper and tap water. As John mentions ammonia is a traditional plasticizer for wood bending - I haven't tried it yet but I also haven't bent figured maple sides yet.

One other thing that I found helpful was having some additional depth on the form, say 1"-2" past the centerline of the body, so that the ends of the side have some space to lay flat past that point.

I looked long and hard for springs when I built mine, and then later discovered that local auto parts stores carry an assortment so you can play with them to figure out what might work.

And for the record, here is my bender. There are extra springs because i use it also to bend ukulele sides, with a sort of plinth to raise the smaller uke form so the cauls can fit over it. I tried several different "layer" configurations but now use a spring steel slat on top, then the blanket, then a third slat (just flashing) between the blanket and wood (I sometimes get light scorch lines from the heating elements in the blanket) and dampened kitchen parchment on both faces of the wood, and another spring slat on the bottom. Bruce W.

Thanks for the help & inspiration everyone. Here's where I'm at now:
I will add some ammonia to the spray bottle.
I do have a full width caul for the waist bend.
I also have some wood crosspieces under the body centerline at each end for extra side support.
I will definitely use springs to hold the end clamp blocks in place. It was a bad mistake for me to use the fiddly eye bolts in the first attempt. It is too cold here today for me to venture into the city looking for springs but next week should be good.

Here's a shot of my set up. The jig is clamped in a swivel vise for easy access to both ends.

Just for reference, if you can't find springs locally, try https://www.mcmaster.com/ . They have springs...and everything else.

Unfortunately, McMaster Carr won't ship to me as I am in Canada. I found that out when I tried to order the pulleys & V Belt I needed when I built my thickness sander.

I have seen the springs at Lordco and Bumper to Bumper in the small town where I live - in Canada - and also some pulleys etc. I've also found Home Hardware pretty good if you search their web site.